Lack of Sleep Is Ruled Factor in 2013 UPS Plane Crash

WASHINGTON — Short of sleep, confused about their altitude and relying on inaccurate weather information, the crew members of a UPS cargo plane trying to land at the airport in Birmingham, Ala., omitted several crucial steps that might have kept them from flying their aircraft into the ground in August 2013, investigators of the National Transportation Safety Board said Tuesday.

An onboard system intended to prevent this kind of accident might have saved them, investigators said, but gave an inadequate warning because the software was old. The airplane, an Airbus A300, also carried a system that automatically called out height during approach, but it was turned off.

The crash, on Aug. 14, 2013, has reopened a debate about fatigue in the cockpit, especially for package-haulers, who fly mostly at night. Early this year, the Federal Aviation Administration revised the limits on scheduling for passenger carriers but exempted cargo airlines, infuriating pilot unions at the cargo carriers. The safety board said the schedules flown by the crew members in this accident would have come close to meeting the new standards anyway, if they had been in force at the time of the crash.

The co-pilot, who failed to call out altitudes she was supposed to read off the altimeter at specified intervals, among other failings, had time to rest the previous day but went to visit a friend instead, investigators said; one investigator called it “off-duty time mismanagement.” After a crash, the safety board looks at hotel records, cellphone calls and text messages to try to determine whether a pilot got enough rest. The pilot and co-pilot died in the crash.

The plane came down outside the fence on the north side of Birmingham-Shuttlesworth International Airport, hitting the trees and then the ground, exploding in a fireball. With airport surveillance cameras, investigators used light from the post-crash fire to determine that the cloud ceiling was about 350 feet; the weather briefings they received said the ceiling might be at 300. The crew, investigators said, evidently believed that it would have plenty of time when the aircraft broke out of the clouds to find the runway.

Exactly how to approach the fatigue problem was not clear. The UPS airline allows pilots to call in and say they are too tired to fly, but investigators cited a survey taken by the union, the Independent Pilots Association, in which 88 percent of the pilots agreed that calling in fatigued “invites adverse scrutiny.”

The airline disputed the safety board’s conclusion that fatigue played a role. “It is difficult to understand how the N.T.S.B. reached its conclusion regarding fatigue related to night flying when the pilot had not flown in 10 days and the first officer was off eight of the previous 10 days,” the airline said in a statement. “We believe these facts — and others — don’t support such a finding.”

One of the four board members, Robert L. Sumwalt, a former airline captain, said that UPS should “go back and fix the culture of this company,” so that pilots would feel more free to take themselves off the flight line. He also criticized UPS for not using up-to-date software on its enhanced ground proximity warning system, which senses the plane’s location by GPS, and compares it to a database of the terrain.

“If they had an iPhone, I can guarantee you they would keep their software up-to-date,” Mr. Sumwalt said.

The runway in Birmingham with a full instrument landing system was out of service overnight, for repairs. The runway the crew intended to use did not have an electronic system to give vertical guidance. The UPS airplane can generate that guidance internally, but the crew set up the cockpit computers improperly, so the guidance did not work. The captain decided to continue the approach anyway, and set a steep rate of descent because, as he said repeatedly on remarks captured by the cockpit voice recorder, air traffic controllers had kept them too high for too long.

The fatigue dispute sidelined major players in the investigation. The safety board normally conducts an investigation with the assistance of other parties, including the Federal Aviation Administration, the airline, the union, the aircraft manufacturer, and, where relevant, the airport authority and the maker of the engines and various components. But the board jealously guards its prerogative to decide what information will be released, and to reach conclusions, and will occasionally eject parties that do not follow its rules.

In this case, it took the unusual step of removing two parties, the airline and the pilots’ union, when they began squabbling over whether fatigue was a factor. The Independent Pilots Association issued a statement saying there was “no doubt” that fatigue was a factor, and UPS publicly rebutted the assertion. According to the airline, its typical pilot is on duty 70 hours a month and flies about 30 hours, and the cockpit crew members’ maximum workday is 13.5 hours, “well inside the F.A.A.’s 16-hour limit.” Crews are given rest periods 25 percent to 50 percent longer than required by F.A.A. regulations, the airline said.

It is an intermediate point in a long argument. Previously, the company has pointed out that it provides places for pilots to rest or sleep; the pilots say this is only because they won that in collective bargaining.

On the day of the crash, as the plane was being loaded in Louisville, Ky., Capt. Cerea Beal Jr. and the first officer, Shanda Fanning, completed some preflight checks and started talking about their work schedules, and how the rules for pilots of passenger planes had changed.

“Ah, the passenger side, you know the new rules they’re gonna make out,” said Captain Beal, according to the cockpit voice recorder transcript released by the National Transportation Safety Board.

“They’re gonna make out,” Ms. Fanning replied.

“Yeah, we need that, too,” Captain Beal said. “I mean, I don’t get that. You know it should be one level of safety for everybody.”

“It makes no sense at all,” Ms. Fanning said.

“No it doesn’t at all,” Captain Beal said.

The two had started work at 9:30 p.m. in Rockford, Ill.

A version of this article appears in print on , Section A, Page 20 of the New York edition with the headline: Lack of Sleep Is Ruled Factor in 2013 UPS Plane Crash. Order Reprints | Today’s Paper | Subscribe